Matter

The official definition of matter is anything that occupies mass and space. These are often building blocks for physical stuffs.

Interestingly enough, Photons and other related non-mass or non-spacial particles are not a form of matter.

Matter can also be broken down into several states:

States of Matter:

Classic States:

1. Solid -> “Has a fixed shape and a fixed volume”. These are tightly packed atoms giving it a definite shape.
2. Liquid -> “Has a fixed volume but not a fixed shape”. These atoms are generally loosely bound together by atomic-atomic bonds.
3. Gases -> “No fixed volume or shape.” The atoms aren’t really bonded together.

Hidden/Extra States

Exotic States

1. Plasma
2. Bose-Einstein Condensate
3. Fermionic Condensate

Condensed Matter Phases

1. Liquid Crystals
2. Amorphous Solids
3. Magnetically Ordered Phases

Extreme States

1. Quark-Gluon Plasma
2. Degenerate Matter
3. Supersolid
4. Superfluid

Hypothetical States:

1. Time Crystals
2. Photonic Matter -> Scientists can trap Photons into ultra-cooled clouds of atoms slowing the photons down. These can then interact with each other as if they have a mass.
3. Rydberg Matter

Theoretical States:

1. String-Net Liquid
2. Exotic Matter

Microsoft just invented one too - Topological State?!

Substances

Within a sample, we can classify different types of matter. Matter can be classified based on its composition and appearance.

1. Homogeneous Matter

• Definition: Matter that has only one visible phase.
• Looks uniform throughout.
• Even if it’s a mixture, the components are evenly distributed.
• ✅ Examples: Saltwater, air, brass (a metal alloy)

2. Heterogeneous Matter

• Definition: Matter with two or more visible phases.
• You can see different parts or areas with different properties.
• ✅ Examples: Salad, oil and water, granite

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Pure Substances vs Mixtures

Type	Description	Examples
Pure Substance	Matter with a fixed composition and distinct properties.	Water (H₂O), Oxygen (O₂), Salt (NaCl)
Mixture	Matter made of two or more substances physically combined. Composition can vary.	Air, salad, seawater

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Pure Substances

A pure substance has a fixed composition and the same properties throughout.

Types of Pure Substances

1. Elements

• Definition: A pure substance made of only one kind of atom.
• Cannot be broken down into simpler substances.
• ✅ Examples: Oxygen (O₂), Gold (Au), Helium (He)
• All atoms in an element have the same number of protons.

2. Compounds

• Definition: A pure substance made of two or more different elements chemically combined.
• Can be broken down into simpler substances (elements) through chemical reactions.
• Properties of compounds are different from the properties of the elements that make them.
• ✅ Examples: Water (H₂O), Carbon Dioxide (CO₂), Sodium Chloride (NaCl)
• Compounds always have a fixed formula (water is always H₂O).

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